1. Field of the Invention
The present invention relates to an electrical connector, and particularly to an electrical connector having a plurality of minimal wiping terminals for electrically connecting an electronic package such as a land grid array (LGA) central processing unit (CPU) with a circuit substrate such as a printed circuit board (PCB).
2. Description of the Prior Art
Electrical connectors are widely used in electrically connecting electronic packages such as land grid array (LGA) central processing units (CPUs) with circuit substrates such as printed circuit boards (PCBs). Patented examples of such electrical connectors are disclosed in U.S. Pat. Nos. 4,553,192 and 6,296,495.
Referring to FIGS. 8 and 9, a conventional electrical connector 9 connects a CPU 8 with a PCB 7. The connector 9 comprises an insulative housing 91, and a multiplicity of terminals 92 received in the housing 91. The housing 91 defines a multiplicity of passageways 910 therethrough, for receiving a corresponding number of the terminals 92 therein.
Each terminal 92 comprises a retaining body 920 engagingly received in a corresponding passageway 910, a soldering portion 921 extending from a bottom end of the retaining body 920, and a cantilever 922 extending slantingly upwardly from a top end of the retaining body 920. The soldering portion 921 electrically connects with the PCB 7 via a solder ball 926. The cantilever 922 protrudes out from a top surface of the housing 91, and has a contacting portion 924 at a distal end thereof for electrically connecting with a corresponding metal contact pad 80 of the CPU 8. The connector 9 thus electrically connects the CPU 8 with the PCB 7.
With the prevailing trend toward miniaturization of computers, the sizes of electrical connectors used in computers are steadily becoming smaller. In contrast, the number of contacts used in modern electrical connectors is increasing to meet the growing need for more signal transmission. Accordingly, the terminal 92 may often be fabricated to be miniaturized, with the cantilever 922 being correspondingly small. When the contacting portion 924 of the terminal 92 engages with the pad 80, the cantilever 922 rotates about a junction of the cantilever 922 and the retaining body 920. The rotation comprises a horizontal displacement component and a vertical displacement component. The effect of the horizontal displacement is to make the contacting portion 924 frictionally wipe the pad 80. Particularly after repeated use of the connector 9, the wiping can result in poor connection between the contacting portion 924 and the pad 80.
In view of the above, a new electrical connector that overcomes the above-mentioned disadvantages is desired.